We moved the shortcircuit package from hadoop-hdfs to hadoop-hdfs-client module in JIRA HDFS-8934 and HDFS-8951, and BlockReader in HDFS-8925. Meanwhile, we also replaced the log4j log with slf4j logger. There were existing code in the client package to guard the log when calling LOG.debug() and LOG.trace(), e.g. in ShortCircuitCache.java, we have code like this:
In slf4j, this kind of guard is not necessary. We should clean the code by removing the guard from the client package.